President Obama insisted Sunday that there will be no White House or political influence on the FBI or the Justice Department as they look into the security of the private email system Hillary Clinton used for government work when she was secretary of state.

"I can guarantee that," Obama said in an interview with "Fox News Sunday." It was his first interview with the network in two years.

Obama also defended his former secretary of state, even as he said that he had to be "careful" because of the ongoing investigation. He strongly suggested that the mishandled classified documents that have come to light in a review of Clinton's unorthodox email system were not the nation's most highly guarded secrets.

"I continue to believe that she has not jeopardized America's national security," the president said, though he noted that "there was a carelessness in terms of managing emails." Clinton has already acknowledged that.

"I also think it's important to keep this in perspective," Obama added, saying that the Democratic presidential front-runner "did an outstanding job" as secretary of state.

Clinton's decision to use a privately owned and managed system for all her email, personal and private, hangs over her candidacy. Classified information was found in an after-the-fact security review of emails to and from Clinton when she was secretary of state, between 2009 and 2013. She has said that bypassing the State Department email system was a mistake but insisted as recently as last week that there is no chance she will be indicted as a result of the FBI inquiry.

Obama also said that he will not pull the Supreme Court nomination of Merrick Garland under any circumstances, including if Clinton is elected in the fall and Garland's nomination is still pending.

"Absolutely not," Obama said in response to a question about whether he might yank the nomination before he leaves office.

Revoking the nomination after a Clinton victory would give her an opportunity to name her own nominee, but Obama was emphatic in ruling that out.

In the interview, the president gave one of his most thorough explanations of his view on countering terrorism, saying that the U.S. response should be true to American values and laws and not rooted in fear.

"It has been my view consistently that the job of the terrorists, in their minds, is to induce panic, induce fear, get societies to change who they are," Obama said.

"And what I've tried to communicate is, 'You can't change us. You can kill some of us, but we will hunt you down, and we will get you.' And, in the meantime, just as we did in Boston, after the marathon bombing, we're going to go to a ballgame."